I bought a 99 sportsman 500, the machine is in great shape. I went through it with and everything seams to work, so I thought. I jacked it up to test the awd, worked great. Took in the mud, the awd worked then stopped working. I jacked it up today and the awd works sluggish on the left (sitting on the machine), I can stop the tire by hand. And the right hardly turns. I've read up on the problems with the speedo and the awd, my speedo doesn't work. Anybody got some troubleshooting ideas?

 

If the speedo does not work you would have no front wheel drive at all. I have awd and the only thing on my speedo that works is its lights and Hour meter because my speedo is fine but my wheel sensor (Hall Effect) that sends the info from the front brake rotor to the speedo quit working.

I onces had one front wheel acting up and changing the hub AWD fluid with clean new stuff cleared it up.

Here is a good link on how the locking hubs work. ATV Time :: View topic - Polaris Demand Drive Hub Q&A Picture Guide to Service

 

My speedo is the same but the light works and the needle shows whatever speed it wants. The odometer doesn't work at all.

 

That means your wheel sensor is bad not your Speedo so it should be not your AWD problem.

Try changing your hub fluids first. Just drain the old stuff out through the hubs Allen screw hole and re fill and let drain at the 3 or 4 O'Clock postions,the proper amount is important.

The above link will show you how.